The ecologist […] must study the order of succession of the plant societies in the development of a region, and he must endeavor to discover the laws which govern the panoramic changes.

Cowles, H.C. (1899). The ecological relations of the vegetation on the sand dunes of Lake Michigan, Part I. Bot. Gaz. 27, 95-117: 95; cf. id. (1901). The physiographic ecology of Chicago and vicinity. A study of the origin, development, and classification of plant societies. Bot. Gaz. 31, 170-177.

1899

plant societies

Cowles, H.C. (1899). The ecological relations of the vegetation on the sand dunes of Lake Michigan, Part I. Bot. Gaz. 27, 95-117: 95; id. (1901). The physiographic ecology of Chicago and vicinity. A study of the origin, development, and classification of plant societies. Bot. Gaz. 31,170-177.